Q: I have always believed that during a workout you are supposed to exhale through the mouth on exertion and inhale through the nose on the way back up. Then yesterday I read in a weight training book that you are supposed to breathe naturally and that exhaling during exertion (followed by inhaling through the nose) is only needed for those people that are lifting really heavy weights to give them a boost during the lifting part. Which is true?

A: I recommend continuing what you've always done -- exhale forcefully through the mouth on exertion (concentric phase) and inhale through the nose during the eccentric phase. This advice is completely universal and is an excellent habit to get into, whether you're in the gym or moving furniture around the house.

Some lifters like to hold their breath during the very heavy lifts which actually helps a little bit, but also spikes your blood pressure for a second up to 50% or more, has some chance of a blackout, and is certainly not necessary for the vast majority of lifters. Continue doing what you've already been doing as far as breathing.